Match ends, Livingston 0, Morton 1.
A Thomas O'Ware header in 64 minutes was enough to take Morton through to the fifth round of the Scottish Cup.
The central defender got on the end of Ross Forbes inswinging corner to claim the only goal of the game.
It was the Greenock side's third win of the season against their Championship rivals.
Livingston are struggling near the foot of the table but can be encouraged by their fighting if ultimately futile performance.
Experienced midfielder Mark Fotheringham picked up a booking in his first game back at Livingston but both he and Sam Stanton showed they can be important additions for David Hopkin.
The on-loan Hibernian youngster brought a touch of class to the midfield while Fotheringham provided steel in the holding role as well as decent delivery from set pieces.
They had their work cut out against a Morton side who dominated possession in the first half but failed to make the most of it.
Forbes sent a swerving 25-yard free kick just past the post on 18 minutes but should have done better from much closer 10 minutes from the break.
Right-back Connor Pepper was a constant threat on the counter-attack and his sweeping cross picked out Forbes only for him to knock the ball wide from six yards.
Livingston were largely restricted to long range efforts with Liam Buchanan twice failing to hit target while Stanton's shot was straight at Derek Gaston.
The second half followed a similar pattern and it was no surprise that Morton's decisive goal came from a set piece situation.
Forbes delivery from corners caused problems all day but never more so than in 64 minutes when he found O'Ware in the six yard box to score with a powerful header.
Buchanan squandered Livingston's best chance of taking the tie to a replay and it does not get any easier for them in the league as it's Rangers away next followed by Falkirk at home.
- 7PittmanSubstituted forKnoxat 83'minutes
- 8FotheringhamBooked at 22mins
- 10MullenSubstituted forCurrieat 85'minutes
- 18SheerinSubstituted forWhiteat 67'minutesBooked at 69mins
- 15PepperBooked at 90mins
- 17RussellBooked at 72mins
- 7McKeeBooked at 63mins
- 8ForbesSubstituted forLamieat 86'minutes
- Craig Charleston
- Shots on Target
Second Half ends, Livingston 0, Morton 1.
Conor Pepper (Morton) is shown the yellow card for a bad foul.
Liam Buchanan (Livingston) wins a free kick in the defensive half.
Foul by Conor Pepper (Morton).
Matthew Knox (Livingston) wins a free kick in the defensive half.
Foul by Conor Pepper (Morton).
Attempt saved. Mark Russell (Morton) right footed shot from outside the box is saved in the bottom right corner.
Substitution, Morton. Ricki Lamie replaces Ross Forbes.
Substitution, Livingston. Ryan Currie replaces Daniel Mullen.
Attempt missed. Liam Buchanan (Livingston) right footed shot from outside the box is close, but misses the top right corner.
Attempt saved. Declan McManus (Morton) left footed shot from a difficult angle on the left is saved in the centre of the goal.
Corner, Livingston. Conceded by Joe McKee.
Substitution, Livingston. Matthew Knox replaces Scott Pittman.
Attempt blocked. Daniel Mullen (Livingston) left footed shot from outside the box is blocked.
Corner, Livingston. Conceded by Lee Kilday.
Attempt blocked. Samuel Stanton (Livingston) header from the centre of the box is blocked.
Corner, Livingston. Conceded by Luca Gasparotto.
Scott Pittman (Livingston) wins a free kick in the attacking half.
Foul by Declan McManus (Morton).